Pernicious Anaemia Society

RDW Range B12

Another GP described, As my RDW is 13.1 Range 11-14.50 you would have noticed a rise in the Red cell Distribution Width, so this is why the conclusion was made that the B12 Result is in Normal Range

( B12 Serum equivalent to* 114pmol/L *)

155ng/L Range 130-800 as some Labs start at 200-900ng/L and mine happens to be as i have been explained the more generous Range.



7 Replies

Don't really follow and does sound like a bit of gobbledygook to me.

Labs do have different ranges because they will be using slightly different equipment with different ways of analysing things.

Comments on RDW sounds as if someone is confusing B12D with anaemia - in the anaemia associated with B12D there is a tendency for red blood cells to be slightly larger and flatter - less surface area so can carry less oxygen which can explain some of the symptoms associated with anaemia.

However, anaemia is a result of B12D - not a defining characteristic. Many people experience neurological and neuropsychiatric and other symptoms long before any signs of anaemia develop. This is particularly true if folate levels are good - and with access to fresh vegetables and fruit having changed so much in the last 50 years, along with fortification of cereals etc that is often the case.


Hi Gambit62 ,

you make some interesting points and i was told from my result at 155ng/L range 130-800 i DONT have an Anemia problem,

And its at this level range due to everybody is different in the process of

Heamoglobin and B12 and this is a generous Range and although i mentioned

the B12 Active test and the MMA test and Homocysteine Test.No further investigation needed.

GP said no need to supplement either just do a B12 Test every 6 months of each year. I did mention BCSH guidelines if under 200ng/L should be treated but it was explained Labs have different Ranges and the B12 issue is very controversial at best.



Really sorry that you find yourself caught up in this.

Any chance that you could may be try and see a different GP - really does sound as if your GP doesn't have a clue that B12D is anything other than a type of anaemia.

The BCSH guidelines - and in fact the NICE guidelines (though they are pretty confusing) - actually recommend treating on the basis of symptoms rather than test results as there isn't a gold standard test for B12 deficiency and the risks of permanent neurological damage if someone is exhibiting neurological symptoms far outweigh the costs of at least trialing B12.


Yes Gambit62 GP did agree on the significance and importance in recommending treating on the basis of symptoms, but that's as far

as it went !It may be worth my while taking the B12 Active Test

Privately rather than with NHS other wise i will be chasing my tale!

I've never seen so many different conflicting views from doctors

Neurologists from different parts of the world since i opened this can of worms!I thought it would of been straight forward.And the GP would do further tests or agree to start supplementing

No need to supplement i'm told.As its a Normal result.

Back in no mans land .


Hi Gambit62

I spoke with a Professor Consultant Neurologist

and he agrees any question of B12 deficiency

in patients they are treated with B12 Injections indefinitely, although many will stop treatment once levels are in Normal Ranges again.



Hope you do manage to get through to your GP


Thank-you Gambit62 for all your kind help

and for your input to others and myself on this forum

which is very important ,i will be seeing another GP and

getting through may be challenging but i remain positive!

we will see.



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